Averaging extensions - Metasys - LIT-12012116 - Server - Metasys UI - 7.0

Johnson Controls System Configuration Tool (JCT) Help

Brand
Metasys
Product name
Metasys UI
Document type
User Guide
Document number
LIT-12012116
Version
7.0
Revision date
2023-09-01
Language
English

The Averaging extension calculates the average, minimum, and maximum value of an attribute over a specific interval (for example, space temperature over 24 hours). The extension is able to sample Boolean, Integer, Unsigned, Enumerated, or Float attribute value types for any extendable objects within a BACnet device.

Averaging Extensions contain attributes common to Metasys system objects. The following table lists the attributes specific to the Averaging extension.

Note: In the Notes column, letters indicate the following: C - Configurable, D - Default Attribute for Display, N - Value Not Required, R - Affected by Extension’s Reliability, W - Writable.
Table 1. Averaging extension attributes

Attribute name

Notes

Initial value

Values/Options/Range

Description

Input Reference

C

   

Max Value Timestamp

 

Invalid DateTime

If Average Value, Minimum Value, or Maximum Value is Unreliable, the timestamp is Undefined.

Min Value Timestamp

 

Invalid DateTime

If Average Value, Minimum Value, or Maximum Value is Unreliable, the timestamp is Undefined.

Object Property Ref

     

Valid Samples

     

If any of these variables are Unreliable and a BACnet read is performed on the following three attributes, the values returned are NaN for Average Value, -INF for Minimum Value, and INF for Maximum Value. If these values are Unreliable and a BACnet read is not performed, the attributes return zero.

Average Value

D,R

NaN

Units of the extended attribute

Maximum Value

R

-INF

Units of the extended attribute

Minimum Value

R

INF

Units of the extended attribute

If any of the following three attributes are written or changed, all samples in the sampling buffer become invalid (set to zero, NaN, -INF, or INF), which makes them Undefined for the UI.

Attempted Samples

W

 

The only acceptable value that can be written to this property is zero using the Clear command.

Window Interval

C,W

3,600

Units = seconds

Range: 900–360,060

Window Samples

C,W

15

Range: 2–200

The following four attributes do not appear in a view, but may be scheduled, trended, and so on.

COV Increment

C,W

0.01

Any value > 0

Floating point value of the Display Precision.

Display Precision

C,W

100ths

Uses Display Precision (Set 0).

Reliability

 

Reliable

Uses Reliability (Set 503).

Units

 

No Units

Units of the extended attribute

The following table lists the commands supported by the Averaging extension.

Table 2. Averaging extension commands

Command name

Parameters

Description

Enable

None

Disable

None

Clear

None